1. Field of the Invention
This invention relates to a sticklike playing instrument (hereinafter simply referred to as "stick") for use in the games of ice hockey, cricket and the like, and more particularly to a stick having puck- or ball-striking surfaces reinforced with a fiber reinforced plastic plate. There will be described hereunder a representative stick which is used in a game of ice hockey.
2. Brief Description of the Prior Art
Heretofore, a stick of this type has been used, for example, in the game of ice hockey. The ice hockey stick is an instrument for striking a disk-shaped puck hard with a radical powerful swing and striking back a puck coming at a high speed. Therefore, the ice hockey stick is easily broken. As a result of our study about the consumption of sticks in Japan, it was found that a university student consumed 30 sticks on average in one season and a player who belongs to a company consumed about 100-150 pcs.
Because of the reasons mentioned above, many attempts have been made to improve a stick which was once simply made of wood. As a result, there appeared a stick reinforced with fiber reinforced plastic (FRP), a stick made of aluminum alloy, a stick made of glass fiber, etc. However, a strong stick often became too heavy for ordinary players, whereas a light-weight stick was often insufficient in durability.
Furthermore, since a stick made of metal such as aluminum alloy is susceptible to plastic deformation, there are used many sticks which are formed by attaching glass fiber reinforced plastic (GFRP) plate, carbon fiber reinforced plastic (CRFP) plate, or the like obtained by impregnating a thermosetting resin such as epoxy, polyester, or the like to a cloth fiber such as glass fiber, carbon fiber, or the like and then hardened to both surfaces of a wooden core material. A typical example of this type is disclosed in U.S. Pat. No. 4,537,398.
The wooden core material has grains oriented in the longitudinal direction of a blade. Such wooden core material is covered with a fiber reinforced plastic plate as a reinforcement plate. The fiber reinforced plastic plate is formed of a plurality of vertical and horizontal fibers which are woven together in such a way as that the vertical and horizontal fibers are intersected with each other and which are then impregnated with resin such as epoxy or the like. However, when a stick with such reinforcement is actually used, it becomes clear that such reinforcement as mentioned alone is not sufficient yet. Since grains are oriented in the longitudinal direction of the blade and the thickness of the stick is rather thin considering its length, it hardly bears a puck impact and is easily broken in the direction of its width. Since it has such characteristic as easily broken in the grain direction it is often split finely or torn.
The cloth type fiber reinforced plastic plate has such an advantage as to reinforce both the vertical and horizontal directions simultaneously because the fibers are intersected with each other in the vertical and horizontal directions. On the other hand, it has such a disadvantage as that the tensile force of the fibers are insufficient because the vertical and horizontal fibers are intersected overlapping with each other and undulated in a waveform. Therefore, it has insufficient tensile strength and insufficient elastic modulus in both vertical and horizontal directions and a physical strength thereof is not large enough. In addition, it has such shortcomings as that a repulsive force against flexibility is small and a responding speed for striking back a puck and a puck speed are slow. Moreover, since fibers are intersected overlapping with each other, it is obliged to have an excessive thickness to that extent. Therefore, the quantity of resin required for impregnation becomes larger to that extent and thus becomes heavier, which naturally spoils an easy handling of such stick. In addition, since a stress concentrates on a point where the fibers are intersected with each other, that portion becomes easy to break.
As a prior art for solving the above shortcomings, there is Japanese patent publication No. Sho 61-59149 filed by the applicant of the present application. The feature of this prior art is that fibers are arranged in parallel relation and extended copying along the configuration of a stick at the puck striking side from a puck striking portion to a handle portion.
However, since the front end portion of a stick, i.e., the area in the vicinity of the toe portion of a blade, is away from a grip portion, the bending amount is large at the time when the blade strikes a puck and delay of response is significant. Moreover, it does not offer a satisfactory solution to such kind of a problem as a difficulty in increasing the puck speed.
The present invention was accomplished in order to solve the above-mentioned problems or shortcomings inherent in the prior art.